Historic Background
Boxing was the first sport to introduce some kind of mouth protection in the late 1920's and early 1930's.1 It was "a rubber guard that helped prevent chipped teeth and cut lips resulting from blows to the head". After World War II organized sport began to flourish. Popularity of team sports on college and professional level increased steadily. The 1954-1955 Handbook of the National Federation of State High School Associations noted that facial and dental injuries accounted for more than 50% of all football injuries.2 Helmets with face masks were not effective in reducing dental trauma. In 1962 finally the National Alliance Football Rules Committee adopted a rule stating that "each player shall wear an intraoral mouth and tooth protection which includes an occlusal and a labial portion". The National Collegiate Athletic Association was extremely hesitant to adopt a similar ruling, although there had been a marked reduction of dental injuries in high school football after 1962. Research had also suggested that mouth guards were effective in reducing the concussion risk due to elevated ICP after blows to the chin. One of the major concerns of the NCAA committee was impairment of speech and performance. Finally in 1974 it was demonstrated that properly fitted mouth guards allow clear speech and mouth guards became mandatory for college football. It was the personal effort and enthusiasm of a single dentist, Cosmo R. Castaldi, that made mouth guards mandatory in Hockey in 1976.
In 1983 the Academy of Sports Dentistry was founded in San Antonio, Texas.3 The academy's purpose is the prevention of oral and facial injuries during athletic endeveaors. One of the last rulings is the 1990 NCAA rule that makes it mandatory that mouth guards be "yellow or any other readily visible color". A spin-off of this regulation is that mouth guards now are requested in team colors. More and more professional and college players are seen wearing mouth guards. This could drastically improve the compliance with mouth protection.
American Academy of Pediatrics Classification of Sports
| Classification | Sports |
| Contact/Collision | Boxing, field hockey, football, ice hockey, lacrosse, martial arts, rodeo, soccer, wrestling |
| Limited Contact/Impact | Baseball, basketball, bicycling, diving, field events, gymnastics, horseback riding, skating, skiing, softball, squash, volleyball |
| Strenuous Noncontact | Aerobic dancing, crew, fencing, running, swimming, tennis, track, weight lifting |
| Moderately Strenuous Contact | Badminton, curling, table tennis |
| Nonstrenuous Contact | Archery, golf, riflery |
Advantages of Mouth Guards
1. They prevent the tongue, lips and cheeks from being lacerated against the sharp edges of the maxillary teeth.4
2. They lessen the risk of injury to the anterior maxillary teeth by about 90%.4
3. They lessen the risk of damage to the posterior teeth of either jaw following a blow delivered to the inferior aspect of the mandible which causes traumatic closure of the mandible to occur. Such an impact can cause cusp fractures and tooth infractions.4
4. They lessen the risk of jaw fractures by absorbing the energy of a traumatic blow to the chin.2
5. They lessen the risk of concussion occurring subsequent to an impact to the mandible from either in front or below because full posterior translation of the condyles is prevented, reducing the level of force transmitted from the condyles to the base of the skull.2,4,5
6. They improve the confidence of players. Athletes concentrate their efforts on the execution of their sport.2,6,7
Types of Mouth Guards
The American Society for Testing And Materials (ASTM) utilizes this classification:
Type I: Stock
Type II: Mouth formed
Type III: Custom-fabricated (over a model)
Stock mouth guards are very inexpensive and readily available. They are however least retentive, most bulky, and interfere with breathing and speech. Some authors consider them to be potentially hazardous and feel they should not be recommended.8,9
Mouth formed mouth guards come in two types. The thermoplastic variety is known as the boil-and-bite technique. The second type II mouth guard is the soft lined variety, that utilizes ethyl methacrylate in a more rigid shell. The lining should be changed before every game, some athletes object to the taste. Type II mouth guards are reasonably priced, and good retention can be achieved if fitted by a dentist. Ranalli demonstrated that unsatisfactory results occur when athletes attempt to fit these mouth guards themselves.9
Type III mouth guards are far superior to types I and II in terms of adaptation, retention, and protection.2,3,8,10 They are fabricated over a dental model using vacuum formed thermoplastic material. One product available commercially uses laminated sheet resin material (Pro-form, Dental Resources 1-800-328-1276). Incorporated between the laminated layers is a brace which is positioned during fabrication about 3 mm from the incisal edges of the maxillary anterior teeth on the palatal side of the mouth guard. The brace serves as an added protection against lingual displacement of teeth during traumatic contact.2
All mouth guards should be stored in a plastic container when not in use to avoid damage due to excessive heat and cold. They should be washed daily in cold or lukewarm water. Hot water may cause distortion. Prior to insertion can be rinsed with any commercially available mouthwash to freshen the taste. As a general rule it is recommended that a standard mouth guard should be replaced after about every two to three years (if not required earlier).4
Special Patient Considerations
Individuals with malocclusions should be identified. Orthodontic evaluation may be indicated. Orthodontic patients with fixed upper and lower appliances are at a higher risk of tearing and bruising their lips. It is recommended to fabricate separate upper and lower mouth guards or a bimaxillary mouth guard.4 Anticipated tooth movement and brackets can be "blocked-out" with silicone putty material, light cured resin, or simply with plaster.2 Removable dentures or orthodontic appliances should not be worn when participating in sports. Dislodgment or breakage of the item have the risk to cause an airway obstruction, especially in the unconscious patient.4
References
1. Boxing. World Book Encyclopedia, vol 2. Chicago, Field Enterprises Educational Corporation, 1973
2. Johnsen, DC, Jackson EW: Prevention of intraoral trauma in sports. Dent Clin North Am 35:657-666, 1991
3. Olin WH: personal communication
4. Chapman PJ: Mouthguards and the role of sporting team dentists. Aust Dent J 34:36-43, 1989
5. Hickey JC, Morris AL, Carlson LD, Seward TE: The relation of mouth protectors to cranial pressure and deformation. JADA 74:735-740, 1967
6. Jakush J: Divergent views:Can dental therapy enhance athletic performance. JADA 104:292-298, 1982
7. Nachman BM, Richardson FS: Football players opinions of mouth guards. JADA 70:62-69, 1965
8. Welburry RR, Murray JJ: Prevention of trauma to teeth. Dent Update 17:117-121, 1990
9. Ranalli DN: Prevention of craniofacial injuries in football. Dent Clin North Am 35:627-645, 1991
10. Pinkham JR: Pediatric dentistry: infancy through adolescence, 2nd ed. WB Saunders Co, 1994
